lab quiz blood pressure, pulse, and blood flow for Anatomy and Physiology II

what is pulse

the alternate expansion and recoil of the arteries that takes place because of the action of the heart

what are pulse points

points on the surface of the body where the pulse may be easily palpated

what are the various pulse point vessels

• superficial temporal artery

• facial artery

• common carotid artery

• radial artery

• brachial artery

• femoral artery

• popliteal artery

• posterior tibial artery

• dorsal pedal artery

what is blood pressure

pressure exerted by the blood against the walls of the arteries

what is systolic pressure

the highest pressure found within the arteries while the left ventricle is ejecting blood into the aorta

what is diastolic pressure

the lowest pressure found in the arteries just before the left ventricle ejects blood (when it is relaxed)

what tool is used to measure blood pressure

sphygmomanometer (blood pressure cuff)

what are the sounds of Korotkoff

• sounds of blood turbulence as it begins leaking through the squeezed brachial artery (systolic pressure/number)

• once enough pressure from the blood pressure cuff is released and the brachial artery is no longer being squeezed, blood turbulence stops and the Korotkoff sounds are gone (diastolic pressure/number)

what is pulse pressure

pulse difference between the systolic and diastolic measurements

how is pulse pressure calculated

• systolic pressure - diastolic pressure = pulse pressure

• i.e. for a 150/90 blood pressure, pulse pressure is 150 - 90 = 60 mmHg

what is mean arterial pressure

• the average pressure found in the arteries

• since the heart is in diastole two thirds of the time and is in systole only one third of the time, you cannot use a simple average of the two to determine the mean arterial pressure

how is mean arterial pressure calculated

• 2/3 diastolic + 1/3 systolic = MAP

• i.e. for a 150/90 blood pressure, MAP = 2/3(90) + 1/3(150) = 110 mmHg

what does a pulse transducer do

measures the variations in blood volume within your finger in order to make a graphic recording

what is plethysmography

the measurement and recording of blood flow within an organ or structure

what kind of change occurs when a person holds their breath

• blood pressure increases

• the body’s response to lower the blood pressure is to decrease heart rate so pulse decreases

when pressure inside the chest is increased by holding your breath, what happens to the venous return of blood to the heart

it decreases

why does the subject’s face turn a darker red when holding their breath

a decrease in venous return of blood to the heart due to increased pressure in the chest means that blood collects in the face

what changes occur in pulse rate/pulse amplitude when a cold water bottle was placed on the subject’s arm

pulse amplitude decreased because the body’s response to the cold water bottle was to vasoconstriction the vessels in the arm to retain heat

what changes occur in pulse rate/pulse amplitude when a warm water bottle was placed on the subject’s arm

pulse amplitude increased because the body’s response to the warm water bottle was to vasodilate the vessels in the arm to release heat

what change occurs in pulse rate/pulse amplitude when the subject lifted and held their hand over their head

pulse amplitude decreased because gravity drained blood from the finger

what change occurs in pulse rate/pulse amplitude when the subject lower and held their hand so it dangled below the lab stool

pulse amplitude increased because gravity pulled blood into the finger where it began to pool

what happens to the pulse in digit five (pinky) when pressure is applied to the radial artery

nothing happens because digit 5 does not receive blood from the radial artery - it receives blood from the ulnar artery

what happens to the pulse in the thumb when pressure is applied to the radial artery

pulse amplitude decreases because the thumb’s blood is supplied by the radial artery

what occurs during venous congestion (pressure which allows arterial flow but hinders venous blood return)

the forearm turns a bluish color

what occurs during ischemia (pressure which does not allow arterial flow) and what happens once arterial flow is no longer restricted

• forearm turns whiteish color/pale

• after deflation, forearm turns very red

why does the arm turn red after deflating the super tight blood pressure cuff (which was used to cause ischemia)

• super tight blood pressure cuff stops arterial flow into the forearm

• tissues in the forearm and hand then send signals saying that they aren’t receiving enough blood

• vessels which bring blood to the forearm (arteries, arterioles, etc.) then dilate in an attempt to receive more blood

• once arterial flow is no longer restricted (blood pressure cuff loosened), a larger-than-usual amount of blood flows into the forearm due to the dilated vessels

• this causes the red color

what is EDV

• end diastolic volume

• amount of blood that fills the heart

what is ESV

• end systolic volume

• amount of blood left in the heart after a ventricle contraction

what is SV

• stroke volume

• amount of blood that exits the heart during a ventricular contraction

• calculated by subtracted the end systolic volume (ESV) from the end diastolic volume (EDV)

• measured in milliliters/beat

• EDV - ESV = SV

what is HR

• heart rate

• number of cardiac cycles per minute

what is CO

• cardiac output

• volume of blood pumped by the ventricle per unit of time

• calculated by multiplying heart rate (HR; beats/minute) by stroke volume (SV; milliliters/beat)

• SV x HR = CO

what is TPR

• total peripheral resistance

• amount of friction encountered by blood as it flows through peripheral blood vessels

• vasodilated vessels have decreased friction so they have a decreased total peripheral resistance

• vasoconstricted vessels have increased friction so they have an increased total peripheral resistance

what is BP

• blood pressure

• amount of lateral pressure exerted by blood on blood vessel walls

• calculated by multiplying cardiac output (CO) by total peripheral resistance (TPR)

• CO x TPR = BP

case study 1: a student rushing to another thrilling physiology lab was not paying attention to her driving and was in an automobile accident in which her wrist was cut and she lost a lot of blood from her radial artery — what is the immediate effect of her blood loss on the total blood volume in her body

decreased total blood volume

case study 1: a student rushing to another thrilling physiology lab was not paying attention to her driving and was in an automobile accident in which her wrist was cut and she lost a lot of blood from her radial artery — before any homeostatic mechanisms kick in, what is the effect of decreased total blood volume on the venous return to the right side of her heart

decreased venous return to right side of heart

case study 1: a student rushing to another thrilling physiology lab was not paying attention to her driving and was in an automobile accident in which her wrist was cut and she lost a lot of blood from her radial artery — is the change in venous return of blood to her heart reflected as a change in EDV or ESV

reflected as a drop in EDV because there’s less blood available in circulation to fill the heart

case study 1: a student rushing to another thrilling physiology lab was not paying attention to her driving and was in an automobile accident in which her wrist was cut and she lost a lot of blood from her radial artery — before any homeostatic mechanisms kick in, what is the effect of her blood loss on her SV

it decreases because less blood fills the heart so less blood is then able to be pumped out of the heart (decreased EDV - ESV = decreased SV)

case study 1: a student rushing to another thrilling physiology lab was not paying attention to her driving and was in an automobile accident in which her wrist was cut and she lost a lot of blood from her radial artery — before any homeostatic mechanisms, what happens to her CO as a result of blood loss

it decreases because the amount of blood that is able to be pumped out of her heart during each contraction decreases (decreased SV x HR = decreased CO)

case study 1: a student rushing to another thrilling physiology lab was not paying attention to her driving and was in an automobile accident in which her wrist was cut and she lost a lot of blood from her radial artery — immediately following her injury, what happened to her BP

it decreased because the amount of blood the heart was pumping out per minute decreased (decreased CO x TPR = decreased BP)

what is the body’s homeostatic response to a decrease in blood pressure

baroreceptor reflex

what are the steps of the baroreceptor reflex pathway

• decrease in blood pressure

• activates baroreceptors (carotid sinus, aortic sinus, also called pressure receptors or stretch receptors)

• baroreceptors detect too little stretch on the carotid and aortic arteries

• baroreceptors generate action potentials

• action potentials travel via CN IX (glossopharyngeal cranial nerve)

• action potentials reach the medulla oblongata

• medulla oblongata stimulates the sympathetic system to become dominant (which results in an increased heart rate, increased ventricular contraction force, and vasoconstriction of peripheral vessels)

• increased blood pressure

case study 1: a student rushing to another thrilling physiology lab was not paying attention to her driving and was in an automobile accident in which her wrist was cut and she lost a lot of blood from her radial artery — what are the effects on her BP once homeostatic mechanisms kick in (baroreceptor reflex)

• ESV is decreased due to an increase in ventricular contraction force

• HR is increased

• TPR is increased due to vasoconstriction of peripheral vessels

case study 1: a student rushing to another thrilling physiology lab was not paying attention to her driving and was in an automobile accident in which her wrist was cut and she lost a lot of blood from her radial artery — what are the effects on her BP once homeostatic mechanisms kick in (baroreceptor reflex) IN ARROW/FORMULA FORMAT

• EDV - decreased ESV = increased SV

• increased SV x increased HR = increased CO

• increased CO x increased TPR = increased BP

case study 1: a student rushing to another thrilling physiology lab was not paying attention to her driving and was in an automobile accident in which her wrist was cut and she lost a lot of blood from her radial artery — despite the homeostatic response (baroreceptor reflex) the patient was unable to maintain her CO and BP — what condition is classified as the general inability to deliver adequate blood and oxygen to the body and what is the specific name of her problem

• general inability is “shock”

• hers is called “hypovolemic shock”

case study 2: an unfortunate patient has had a massive myocardial infarction which killed off part of the heart muscle and leaving part of the ventricle unable to contract — will this damage to the heart muscle be reflected as an increase or decrease to EDV or ESV

increase in ESV - more blood left in the ventricle after contraction

case study 2: an unfortunate patient has had a massive myocardial infarction which killed off part of the heart muscle and leaving part of the ventricle unable to contract — before any homeostatic mechanisms kick in, what is the effect on his SV

• decrease in SV because more blood is not being emptied from the ventricle

• EVD - increased ESV = decreased SV

case study 2: an unfortunate patient has had a massive myocardial infarction which killed off part of the heart muscle and leaving part of the ventricle unable to contract — before any homeostatic mechanisms kick in, what happens to his CO

• decreased CO because the amount of blood leaving the heart each cardiac cycle is decreased

• decreased SV x HR = decreased CO

case study 2: an unfortunate patient has had a massive myocardial infarction which killed off part of the heart muscle and leaving part of the ventricle unable to contract — immediately following his MI, what happens to his BP

• decreased BP because the amount of blood being pumped out of the heart and into circulation per minute is decreased

• decreased CO x TPR = decreased BP

case study 2: an unfortunate patient has had a massive myocardial infarction which killed off part of the heart muscle and leaving part of the ventricle unable to contract — following the baroreceptor reflex (conducted in response to his low BP), what occurs IN ARROW FORMAT

• EDV - ESV = SV * because cardiocytes have died from MI, ESV cannot be increased by the baroreceptor reflex

• SV x increased HR = increased CO

• increased CO x increased TPR = increased BP

case study 2: an unfortunate patient has had a massive myocardial infarction which killed off part of the heart muscle and leaving part of the ventricle unable to contract — what are the effects on her BP once homeostatic mechanisms kick in (baroreceptor reflex)

• force of ventricular contraction cannot be increased by sympathetic system because cardiocytes have died from the MI so ESV doesn’t change

• SV then doesn’t change because there was no change in ESV

• HR increases

• TPR increases because of vasoconstriction of peripheral vessels

case study 2: an unfortunate patient has had a massive myocardial infarction which killed off part of the heart muscle and leaving part of the ventricle unable to contract — despite homeostatic response (baroreceptor reflex), the patient was unable to maintain his CO and BP — what condition is classified as the general inability to deliver adequate blood and oxygen to the body and what is the specific name of his problem

• general inability is called “shock”

• his specific condition is called “cardiogenic shock”

case study 3: a nicotine addict smokes a cigarette and the absorbed nicotine causes the release of norepinephrine and epinephrine into the circulation which then causes sympathetic system dominance — what are the corresponding effects on the heart rate

the heart rate increases and the force of ventricular contraction increases

case study 3: a nicotine addict smokes a cigarette and the absorbed nicotine causes the release of norepinephrine and epinephrine into the circulation which then causes sympathetic system dominance — how is her SV affected

• SV increases because ESV decreases due to increased force of ventricular contraction from sympathetic system dominance

• EDV - decreased ESV = increased SV

case study 3: a nicotine addict smokes a cigarette and the absorbed nicotine causes the release of norepinephrine and epinephrine into the circulation which then causes sympathetic system dominance — how is the blood vessel diameter affected

coronary arteries and skeletal muscle arteries dilate while peripheral vessels constrict

case study 3: a nicotine addict smokes a cigarette and the absorbed nicotine causes the release of norepinephrine and epinephrine into the circulation which then causes sympathetic system dominance — what is the affect of smoking on BP

increased BP

case study 3: a nicotine addict smokes a cigarette and the absorbed nicotine causes the release of norepinephrine and epinephrine into the circulation which then causes sympathetic system dominance — what short-term and long-term affects does smoking have on the cardiovascular system

• short-term effect is hypertension

• long-term effect is a myocardial infarction resulting from prolonged hypertension which may then result in heart failure

case study 3: a nicotine addict smokes a cigarette and the absorbed nicotine causes the release of norepinephrine and epinephrine into the circulation which then causes sympathetic system dominance — what changes occur during this sympathetic system dominance IN ARROW FORMAT

• EDV - decreased ESV = increased SV

• increased SV x increased HR = increased CO

• increased CO x increased TPR = increased BP

case study 3: a nicotine addict smokes a cigarette and the absorbed nicotine causes the release of norepinephrine and epinephrine into the circulation which then causes sympathetic system dominance — what changes occur during this sympathetic system dominance IN EXPLANATION/NOT ARROW FORMAT

• ESV decreases because the force of ventricular contraction increases

• decrease in ESV causes an increase in SV because less blood in the heart after ventricle systole means more blood is being pumped out of the heart during each contraction

• increase in CO because more blood is leaving the heart during contraction (increased SV) and more contractions are occurring per minute (increased HR)

• TPR is increased because peripheral vessels are constricted due to sympathetic dominance

• increased BP because more blood is being pumped from the heart per minute and the peripheral blood vessels are smaller (vasoconstriction; increased TPR)

case study 4: Ms. Athlete and Ms. Couch Potato are both about the same size and, at rest, both of them need about the same CO of around 4800 mL/min, but Ms. Athlete’s resting HR is 60 bpm and Ms. Couch Potato’s resting HR is 80 bpm — if their CO is the same yet Ms. Athlete’s resting HR is lower than Ms. Couch Potato’s resting HR, what do we know about their SV’s

• Ms. Athlete’s SV is higher than Ms. Couch Potato’s

• Ms. Athlete’s heart pumps out more blood during one cardiac cycle than Ms. Couch Potato’s heart, meaning her heart (ventricles) contract more effectively (harder) than Ms. Couch Potato’s

case study 4: Ms. Athlete and Ms. Couch Potato are both about the same size and, at rest, both of them need about the same CO of around 4800 mL/min, but Ms. Athlete’s resting HR is 60 bpm and Ms. Couch Potato’s resting HR is 80 bpm — what changes occur in the heart as a result of consistent aerobic conditioning IN ARROW FORMAT AND EXPLANATION FORMAT

• increased EDV - decreased ESV = increased SV

• heart muscle grows stronger/hypertrophies due to the aerobic conditioning (just as skeletal muscle would)

• this growth in strength of the heart muscle increases the amount of blood that the ventricles are able to pump out during contraction (decreased ESV) which in turn increased the amount of blood that can fill the heart during relaxation (increased EDV)

case study 5: after a long and boring class in a warm room, Woozy Willy stand up very quickly — under normal conditions, which vessels contain most of Willy’s blood volume

veins

case study 5: after a long and boring class in a warm room, Woozy Willy stand up very quickly — what happens to the blood when Willy stands up quickly

blood that has pooled in the legs while sitting (because of gravity and no movement) is not able to reach his brain fast enough once he stands up which then causes dizziness

case study 5: after a long and boring class in a warm room, Woozy Willy stand up very quickly — what effects does Willy’s reduced movement and then standing up too quickly have on Willy’s venous return

decreased venous return because one of the mechanisms the veins rely on to move blood back to the heart against gravity is the skeletal muscle pump which is not utilized when there is no movement

case study 5: after a long and boring class in a warm room, Woozy Willy stand up very quickly — how is Willy’s decrease in venous return after standing up too quickly reflected in heart activity

decreased EDV because not as much blood reaches the heart to fill it during ventricle relaxation

case study 5: after a long and boring class in a warm room, Woozy Willy stand up very quickly — how does the change in Willy’s venous return affect his SV

• decreased SV because not as much blood can fill the heart during relaxation (decreased EDV) meaning not as much blood can then be pumped out of the heart during ventricle contraction (SV)

• decreased EDV - ESV = decreased SV

case study 5: after a long and boring class in a warm room, Woozy Willy stand up very quickly — before any homeostatic mechanisms kick in, what are the effect on Willy’s CO and BP

• decreased CO because not as much blood is being pumped out of the heart during one cardiac cycle (decreased SV) meaning not as much blood is being pumped out of the heart per minute

• decreased SV x HR = decreased CO

• decreased BP because not as much blood is being pumped out of the heart and entering circulation per minute

• decreased CO x TPR = decreased BP

case study 5: after a long and boring class in a warm room, Woozy Willy stand up very quickly — how does the baroreceptor reflex increase Willy’s BP

• increased force of ventricular contraction due to sympathetic system dominance decreases ESV which then increases SV

• increase in HR due to sympathetic system dominance

• increase in SV and HR causes an increased CO because more blood is being pumped out during each cardiac cycle an increased amount of times per minute

• increase in TPR due to vasoconstriction of peripheral vessels from sympathetic system dominance

• increase in CO and increase in TPR causes increase in BP because more blood is being pumped out of the heart and into circulation per minute and vessels receiving the blood have a smaller diameter

what is the body’s homeostatic response to an increase in blood pressure

parasympathetic system dominance caused by baroreceptor reflex

what are the steps of the baroreceptor reflex in response to an increase in blood pressure

• increase in BP

• activates baroreceptors (carotid sinus, aortic sinus, also called pressure receptors or stretch receptors)

• baroreceptors detect too much stretch on carotid and aortic arteries

• baroreceptors generate action potentials

• action potentials travel via CN IX (glossopharyngeal cranial nerve) to medulla oblongata

• medulla oblongata receives action potentials

• medulla oblongata stimulates parasympathetic system to become dominant (which results in a decrease in HR, decrease in force of ventricle contraction, vasodilation of peripheral vessels)

• decrease in BP

what happens as a result of parasympathetic system dominance caused by baroreceptor reflex to increased BP that decreases BP

• decreased force of ventricle contraction from parasympathetic system dominance causes an increase in ESV

• ESV increase causes a decrease in SV

• EDV - increased ESV = decreased SV

• parasympathetic system causes decreased HR

• decreased SV x decreased HR = decreased CO

• vasodilation of peripheral vessels from parasympathetic system dominance causes a decrease in TPR

• decreased CO x decreased TPR = decreased BP

what are the effects of beta blockers on the heart

• blocks the effects of sympathetic innervation to the heart (blocks norepinephrine from binding to beta receptors on the heart)

• increased ESV caused by decreased force of ventricle contraction from blocking of sympathetic innervation

• decreased HR from blocking sympathetic innervation

• EDV - increased ESV = decreased SV

• decreased SV x decreased HR = decreased CO

• decreased CO x TPR = decreased BP

what are the effects of alpha blockers on the heart

• blocks the effects of sympathetic innervation to the blood vessels (blocks epinephrine from binding to alpha receptors on vessels)

• decreased TPR caused by dilation of peripheral vessels from blocking of sympathetic innervation

• CO x decreased TPR = decreased BP

what are the effects of calcium channel blockers on the smooth muscle cells of the blood vessels and the heart muscle cells

• decrease in calcium in the heart’s muscle cells due to channels being blocked reduces good ventricle contraction since calcium is needed for contraction

• decrease in calcium in the smooth muscle cells of blood vessels due to channels being blocked reduces smooth muscle contraction since calcium is needed for contraction which then dilates peripheral blood vessels

• EDV - increased ESV = decreased SV

• decreased SV x HR = decreased CO

• decreased CO x decreased TPR = decreased BP

what are the effects of diuretics on fluid levels and BP

• decrease in fluid levels due to increased urine output caused by diuretics

• blood volume decreases because of increased urine output which then decreases the amount of blood filling the ventricles during relaxation (decreased EDV) which decreases BP

• decreased EDV - ESV = decreased SV

• decreased SV x HR = decreased CO

• decreased CO x TPR = decreased BP